Category Archives: Attribution

Nature Unbound IV – The 2400-year Bray cycle. Part A

By Javier

The existence of a ~ 2400-year climate cycle, discovered in 1968 by Roger Bray, is supported by abundant evidence from vegetation changes, glacier re-advances, atmospheric changes reflected in alterations in wind patterns, oceanic temperature and salinity changes, drift ice abundance, and changes in precipitation and temperature. This is established with proxy records from many parts of the world.

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Nature Unbound III – Holocene climate variability (Part B)

by Javier

The Neoglacial has been a period of progressive cooling, increasing aridity, and advancing glaciers, culminating in the Little Ice Age. The main Holocene climatic cycle of ~ 2400 years delimits periods of more stable climatic conditions which were identified over a century ago. The stable periods are punctuated by abrupt changes.

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Nature Unbound III: Holocene climate variability (Part A)

by Javier

First in a two part series on Holocene climate variability.

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Nature Unbound II: The Dansgaard- Oeschger Cycle

by Javier

Dansgaard-Oeschger (D-O) events are the most dramatic and frequent abrupt climate change events in the geological record. They are usually explained as the result of an Atlantic Ocean salinity oscillation paced by internal variability. Available evidence however supports that they are the result of an externally paced oceanic-sea ice interaction in the Norwegian Sea. A lunisolar tidal cycle provides an unsupported hypothesis that explains all of the known evidence for the 1470-year pacing and the triggering mechanism for D-O oscillations.

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Prospects for a Prolonged Slowdown in Global Warming in the Early 21st Century

by Nic Lewis

[W]e estimate that the warming slowdown (< 0.1 K/decade trend beginning in 1998) could persist, due to internal variability cooling, through 2020, 2025 or 2030 with probabilities 16%, 11%, and 6%, respectively. – Knutson et al.

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Nature Unbound I: The Glacial Cycle

by Javier

Insights into the debate on whether the Holocene will be long or short.

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What is the relationship between Arctic sea ice decline and Eurasian cold winters?

by Judith Curry

We conclude that the observed cooling over central Eurasia was probably due to a sea-ice-independent internally generated circulation pattern ensconced over, and nearby, the Barents–Kara Sea since the 1980s. — McCusker et al.

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